JPH08216547A - Blanket belt for printer and manufacture thereof - Google Patents

Abstract

PURPOSE: To ensure high grade printing quality by the method wherein both the expansion and contraction of a blanket surface and the slipping from a pulley are effectively prevented from occurring. CONSTITUTION: An endless timing belt is constituted so as to be integrally made out of rubber stock for blanket in such a manner that teeth T..., for timing belt are provided on its inner surface, a blanket surface 2 is provided on its outer surface and reinforcing material 3 is embedded within the belt.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blanket belt for a printing machine, which is suitable for producing a blanket belt for an offset printing machine or the like, and a method for producing the blanket belt.

[0002]

2. Description of the Related Art Generally, in an offset printing machine, a plate is wound around a cylindrical plate cylinder and loaded, and an ink image adhered to the plate on the plate cylinder is once transferred (off) to the cylindrical blanket cylinder. At the same time, the ink image transferred to the blanket cylinder is printed (set) on printing paper. Such a blanket cylinder usually has a blanket mounted on the outer peripheral surface, and this blanket is a two-layer structure in which a rubber layer made of nitrile rubber such as NBR is provided on a reinforcement layer for preventing expansion and contraction using cloth or the like. It is formed as a sheet of structure.

On the other hand, since the blanket cylinder uses its peripheral surface, if the size of the printing plate is to be increased, the blanket cylinder will be correspondingly increased, which leads to an increase in the size of the printing machine. For this reason, conventionally, there has been proposed a blanket carrier mechanism constituted by spanning an endless blanket belt between a pair of spaced pulleys instead of the blanket cylinder (see Japanese Patent Laid-Open No. 6-64135).

[0004]

However, when the general blanket mounted on the blanket cylinder is applied to the above-mentioned blanket belt, there is a problem that the following problems occur.

First, when the blanket is mounted on the blanket cylinder, the thickness of the blanket does not matter so much, but when it is used for the blanket belt, the thickness of the blanket causes the blanket belt to be located at the position on the pulley. On the other hand, since the outer surface of the belt expands, and at the position other than the pulley, the contraction occurs due to the reaction, the blanket belt may expand or contract during printing, and as a result, the print quality may be impaired.

Secondly, the movement of the blanket belt and the rotation of the pulley must be perfectly matched (synchronized), but the slippage between the blanket belt and the pulley makes it impossible to move the blanket belt accurately and stably. From this point as well, the print quality may be impaired.

The present invention solves the problems existing in the prior arts described above, and by effectively preventing both expansion and contraction of the blanket surface and sliding on the pulley, a high print quality can always be ensured. An object of the present invention is to provide a blanket belt for a printing machine and a manufacturing method thereof.

[0008]

A blanket belt 1 for a printing press according to the present invention is integrally formed of a blanket rubber material, has teeth T for a timing belt on its inner surface, and has a blanket surface 2 on its outer surface. In addition to being provided, the endless timing belt is configured by including the reinforcing material 3 inside.

In this case, the tooth T ...
Wear the tooth cloth R on. The reinforcing material 3 is a reinforcing core wire or a reinforcing mesh sheet. On the other hand, NBR (nitrile rubber) is used as the blanket rubber material, and the outer surface is formed by polishing to a finished blanket surface.

Further, the method for manufacturing the blanket belt 1 for a printing machine according to the present invention comprises a reinforcing material mounting step P1 for mounting the reinforcing material 3 on a mold having a tooth pattern on the outer peripheral surface, and a reinforcing material mounted on the mold. 3, a rubber sheet mounting step P2 of mounting an unvulcanized rubber sheet using a blanket rubber material,
A vulcanization step P3 in which the intermediate product obtained from the rubber sheet mounting step P2 is vulcanized to form the teeth T for the timing belt on the inner surface and to obtain an endless timing belt having the reinforcing material 3 inside. The blanket surface processing step P4 of processing the outer surface of the timing belt into the blanket surface 2 after vulcanization is included.

In this case, according to the optimum embodiment, the reinforcing material mounting step P1 includes a tooth cloth mounting step of mounting the tooth cloth R on the mold before mounting the reinforcing material 3. Further, the blanket surface processing step P4 includes a polishing step of polishing the outer surface of the timing belt to finish the blanket surface 2. On the other hand, in the reinforcing material mounting step P1, the reinforcing core wire may be wound,
A reinforcing mesh sheet may be wrapped around. NBR is used as the blanket rubber material.

[0012]

According to the blanket belt 1 for a printing press and the method for manufacturing the same according to the present invention, at the time of manufacturing, the reinforcing material 3 is mounted on the mold having the tooth mold on the outer peripheral surface in the reinforcing material mounting step P1. At this time, by the step of attaching the tooth cloth, the reinforcing material 3
It is desirable to mount the tooth cloth R on the mold before mounting. The reinforcing material 3 uses a reinforcing core wire or a reinforcing mesh sheet and is wound around the outer peripheral surface (or the tooth cloth R) of the mold.

On the other hand, in the rubber sheet mounting step P2, an unvulcanized rubber sheet using a blanket rubber material is mounted on the reinforcing material 3 mounted on the mold.

On the other hand, in the vulcanization step P3, the intermediate product obtained in the rubber sheet mounting step P2 is vulcanized. As a result, a part of the rubber sheet passes through the reinforcing material 3 and reaches the outer peripheral surface (or the tooth cloth R) of the mold. Therefore, an endless timing belt having the timing belt teeth T ... on its inner surface and having the reinforcing material 3 inserted therein is obtained.

Then, in the blanket surface processing step P4, the outer surface of the vulcanized timing belt is processed into the blanket surface 2. That is, the blanket belt 1 is obtained by polishing the outer surface of the timing belt to finish the blanket surface 2 in the polishing step.

Since such a blanket belt 1 is configured as an endless timing belt, slippage when it is hung on a pulley is eliminated, and it becomes possible to effectively reduce the thickness by integration, and it is possible to move the belt through the pulley. Expansion and contraction are suppressed, and a high level of print quality is always ensured.

[0017]

Next, preferred embodiments according to the present invention will be described in detail with reference to the drawings.

First, in order to help understanding of the present invention, a general schematic configuration of an offset printing machine will be described with reference to FIG.

The figure shows the internal structure of the offset printing machine M. Reference numeral A denotes a plate carrier mechanism, which includes an endless plate belt 13 spanned between a pair of pulleys (gears) 11 and 12 that are horizontally separated. The plate belt 13 is a timing belt. The plate carrier mechanism A includes a front clamp mechanism 14 and a rear clamp mechanism 15 provided on the plate belt 13, and
A plate clamp device 17 including an operation mechanism 16 provided so as to face the plate belt 13 is provided.

Further, B is an automatic plate feeding mechanism for automatically feeding the plate S to the plate carrier mechanism A. The plate tray 21 accommodates a plurality of plates S ... A separation roller 22 for separating and taking out the sheets one by one, a plate feeding roller mechanism 23 for conveying the plate S taken out from the plate tray 21, and a guide portion 24 for guiding the plate S are provided.

Further, C is an automatic plate discharge mechanism for automatically discharging the plate S from the plate carrier mechanism A, and at the time of discharge, the plate belt 13
Paddle roller 26 for picking up the front part of the plate S which is displaced to the side and released from the plate clamp device 17, a plate discharge roller mechanism 27 for conveying and discharging the scooped plate S, and the discharged plate S
A plate recovery tray 28 for recovering

On the other hand, D is a blanket carrier mechanism,
A pair of pulleys (gears) 31 and 32 are vertically separated from each other, and an endless blanket belt 1 is laid between the pulleys 31 and 32. The blanket belt 1 is a timing belt manufactured by a manufacturing method according to the present invention described later. In this case, the pulley 3 located on the upper side
The blanket belt 1 hung on 1 is in pressure contact with the plate belt 13 hung on the pulley 12 located on the rear side of the plate carrier mechanism A, but can be displaced with the shaft center of the pulley 32 located on the lower side as a fulcrum. When passing through the mechanism 14 and the rear clamp mechanism 15, the cam 33 that follows the rotation of the pulley 12 separates the plate belt 13 from the plate belt 13, and when not in use, the plate belt 13 is locked by a lock mechanism (not shown).
Locked in a position away from.

On the other hand, E is a processing liquid supply mechanism, which is equipped with an etching liquid supply unit 41 containing an etching liquid and a dampening water supply unit 42 containing dampening water, so that the plate S loaded on the plate belt 13 is provided. On the other hand, the etching liquid or the dampening water can be selectively applied. Further, F is an ink supply mechanism, which is configured to be able to apply ink from the ink supply unit 43 to the plate S loaded on the plate belt 13.

Further, G is a printing mechanism, which includes a printing paper tray 51 for accommodating a plurality of printing papers W, a separation roller 52 for separating the printing papers W one by one from the printing paper tray 51, and a printing paper tray. Guide part 53 for guiding the printing paper W taken out from 51, blanket belt 1
Pressure contact roller 54 capable of pressure contact with the surface of the sheet, a paper feed roller mechanism 55 for feeding the printing paper W between the pressure contact roller 54 and the blanket belt 1, the pressure contact roller 54 and the blanket belt 1.
A conveyor belt mechanism 57 is provided for feeding the printing paper W fed from the space to a printing paper collection tray (not shown). Reference numeral 58 is a separation nozzle for ejecting air to separate the printing paper W from the blanket belt 1, and 59 is a suction unit for attracting the printing paper W to the transport belt mechanism 57.

On the other hand, H is a cleaning mechanism, which removes the residual ink on the blanket belt 1 with a cleaning sheet 61 such as cloth supplied from a roll and a cleaning liquid supplied from a cleaning liquid supply unit 62.

Next, with respect to the most suitable method for manufacturing the blanket belt 1 for such an offset printing machine M,
The process will be described with reference to the manufacturing process diagrams shown in FIGS. 2 and 3 and FIG.

First, in the preparation step, the tooth cloth is cut into a desired size (step S01). Then, both ends of the cut tooth cloth are sewn to be endless processed (step S02).

On the other hand, a step S is performed by the step S03 of mounting the tooth cloth.
The tooth cloth R obtained in No. 02 is mounted on a cylindrical mold having a tooth mold on the outer peripheral surface. As the tooth cloth R, it is desirable to use nylon canvas cloth or the like having excellent wear resistance. Also, a mold release agent is applied to the mold in advance. By using such a tooth cloth R, noise can be reduced and durability can be improved.

Then, in the reinforcing material mounting step P1, the reinforcing material 3 is mounted on the tooth cloth R mounted on the mold. That is, a reinforcing fiber such as glass fiber cord, aramid fiber, Kepler fiber, nylon fiber, rayon fiber is wound around the tooth cloth R. By mounting the reinforcing member 3 in this way, expansion and contraction of the blanket surface 2 described later is suppressed. In this case, instead of winding the reinforcing core wire, a reinforcing mesh sheet (cloth sheet or the like) may be wound as shown in FIG. 3 (process PC1). Thereby, expansion and contraction of the blanket surface 2 in the length direction and the width direction are surely suppressed. The reinforcing mesh sheet can also be made of the same material as the reinforcing core wire. In this case, the reinforcing core wire and the reinforcing mesh sheet may be used together.

In the rubber sheet mounting step P2, an unvulcanized rubber sheet made of NBR suitable as a blanket rubber material is wound and mounted on the reinforcing material 3 mounted on the mold.

On the other hand, in the vulcanization step P3, the intermediate product obtained in the rubber sheet mounting step P2 is vulcanized. As a result, a part of the rubber sheet reaches the tooth cloth R through the reinforcing material 3, has the teeth T for the timing belt on the inner surface, and has the endless timing belt with the reinforcing material 3 inserted therein. obtain. It should be noted that steps S03 to P3 are carried out in a state of being attached to the mold. Therefore, when the vulcanization treatment is completed, the mold is released and the molded timing belt is taken out (step S31). Then, in the blanket surface processing step P4, the outer surface of the vulcanized timing belt is processed into the blanket surface 2. That is, by the polishing process,
The outer surface of the timing belt is polished to obtain a blanket surface 2 having high surface accuracy and uniform thickness accuracy. Generally, in a blanket, not only surface accuracy but also thickness accuracy is important, and the thickness excluding the reinforcing material 3 is 1.65 to
1.90 mm is optimal.

When the above steps are completed, predetermined inspections such as slab inspection, length measurement, and appearance inspection are performed (step S41). As a result, the blanket belt 1 shown in FIG. 1 is obtained.

Next, the overall operation of the offset printing machine M using such a blanket belt 1 will be described with reference to FIG.
Will be described with reference to.

First, the plates S are set on the plate tray 21. In this case, as the plate S, a printing paper on which toner is printed by a laser printer or the like can be used. On the other hand, the plate S set on the plate tray 21 is automatically loaded on the surface of the plate belt 13 by the automatic plate feeding mechanism B. That is, at the time of loading, after the front part of the plate S is clamped by the front clamp mechanism 14, the plate S is loaded on the plate belt 13 and the rear part of the plate S is clamped by the rear clamp mechanism 15. . Note that, at the time of loading, the etching process is performed at the same time. In this case, the ink supply mechanism F and the blanket belt 1 are the plate belt 13
Away from. Further, the processing liquid supply mechanism E is the plate belt 1
3 is pressed against the plate 3, and the etching solution supplied from the etching solution supply unit 41 is applied to the plate belt 13. This allows
The dirt and dust on the plate S are removed, and the hydrophilicity is enhanced.

On the other hand, in the printing process, the ink supply mechanism F, the blanket belt 1 and the treatment liquid supply mechanism E are brought into pressure contact with the plate belt 13, respectively. Further, the dampening water supply unit 42 is set to be able to supply the dampening water to the plate belt 13. As a result, when the plate S is moved forward from the standby position, dampening water is applied to the plate S, and further ink is applied from the ink supply mechanism F. At this time, the ink adheres only to the image portion of the plate S. Then, the ink image on the plate S is transferred to the surface of the blanket belt 1. On the other hand, in the printing mechanism G, the printing paper W is fed with the blanket belt 1 and the pressure roller 5
The ink image on the blanket belt 1 is automatically fed to the printing paper W between the four sheets. Such a printing process is repeated for the number of printed sheets.

In this case, the blanket belt 1 according to the present invention eliminates slippage when it is stretched over the pulleys 31 and 32, and can be effectively thinned by being integrated with the timing belt, so that it can be moved through the pulleys. The expansion and contraction of time is suppressed, and high print quality is always ensured.

When the printing of the plate S is completed, the plate belt 1
The plate S loaded in 3 is discharged by the automatic plate discharging mechanism C,
It is collected in the plate collection tray 28. On the other hand, the residual ink on the blanket belt 1 is removed by the cleaning mechanism H.

The embodiment has been described in detail above.
The present invention is not limited to such an embodiment,
The detailed configuration, shape, quantity, material, etc. can be arbitrarily changed without departing from the scope of the present invention.

[0039]

As described above, the blanket belt for a printing machine according to the present invention is integrally formed of a blanket rubber material, has teeth for the timing belt on its inner surface, and has a blanket surface on its outer surface, A reinforcing material is put in to form an endless timing belt, and the method for manufacturing a blanket belt for a printing machine according to the present invention is
Reinforcing material mounting process of mounting a reinforcing material on a mold having a tooth pattern on the outer peripheral surface and rubber sheet mounting of mounting an unvulcanized rubber sheet using a blanket rubber material on the reinforcing material mounted on the mold And a vulcanization step of vulcanizing the intermediate product obtained from the step of mounting the rubber sheet to form teeth for the timing belt on the inner surface and obtaining an endless timing belt having a reinforcing material inside. Since it includes a blanket surface processing process that processes the outer surface of the timing belt into a blanket surface after vulcanization, it is possible to effectively prevent both expansion and contraction of the blanket surface and sliding on the pulley.
It has a remarkable effect of ensuring high print quality.

[Brief description of drawings]

FIG. 1 is a side sectional view of a blanket belt according to the present invention,

FIG. 2 is a manufacturing process diagram of the blanket belt,

FIG. 3 is a partial manufacturing process diagram showing another embodiment of the blanket belt,

FIG. 4 is an internal structure diagram of an offset printing machine using the blanket belt,

[Explanation of symbols]

 1 Blanket belt 2 Blanket surface 3 Reinforcing material T ... Tooth R Teeth P1 Reinforcing material installation process P2 Rubber sheet installation process P3 Vulcanization process P4 Blanket surface processing process

Claims (12)

[Claims] 1. An endless timing belt is formed by integrally forming a blanket rubber material, providing a timing belt tooth on an inner surface, and providing a blanket surface on an outer surface, and a reinforcing material inside. A blanket belt for printing presses that is characterized by 2. The blanket belt for a printing press according to claim 1, wherein a tooth cloth is attached to each tooth. 3. The blanket belt for a printing press according to claim 1, wherein the reinforcing material is a reinforcing core wire. 4. The blanket belt for a printing press according to claim 1, wherein the reinforcing material is a reinforcing mesh sheet. 5. The blanket belt for a printing machine according to claim 1, wherein NBR (nitrile rubber) is used as the blanket rubber material. 6. The blanket belt for a printing press according to claim 1, wherein the outer surface of the timing belt is formed as a blanket surface finished by polishing. 7. A reinforcing material mounting step of mounting a reinforcing material on a mold having a tooth mold on an outer peripheral surface, and an unvulcanized rubber sheet using a blanket rubber material on the reinforcing material mounted on the mold. The step of attaching the rubber sheet and the intermediate product obtained from the step of attaching the rubber sheet are vulcanized to form teeth for the timing belt on the inner surface and to obtain an endless timing belt having a reinforcing material inside. A method for manufacturing a blanket belt for a printing press, comprising a vulcanization step and a blanket surface processing step of processing the outer surface of the timing belt into a blanket surface after vulcanization. 8. The method for manufacturing a blanket belt for a printing press according to claim 7, wherein the step of mounting the reinforcing material includes a step of mounting the tooth cloth on the mold before mounting the reinforcing material. . 9. The method of manufacturing a blanket belt for a printing press according to claim 7, wherein a reinforcing core wire is wound in the step of mounting the reinforcing material. 10. The method for manufacturing a blanket belt for a printing press according to claim 7, wherein a reinforcing mesh sheet is wound in the reinforcing material attaching step. 11. The method of manufacturing a blanket belt for a printing machine according to claim 7, wherein NBR is used as the blanket rubber material. 12. The method of manufacturing a blanket belt for a printing press according to claim 7, wherein the blanket surface processing step includes a polishing step of polishing the outer surface of the timing belt to finish the blanket surface.